KLF4 and ischemic stroke: More recently, we found that the serum level of KLF4 is negatively correlated with infarct volume of acute ischemic stroke (AIS) patients and that KLF4 alleviates cerebral vascular injury by ameliorating vascular endothelial inflammation and regulating tight junction protein expression following ischemic stroke [13, 14], indicating that KLF4 confers vascular protection against cerebral ischemic injury.